<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>函数的参数默认值的优化</title>
    <script>

        function add1(a, b) {
            console.log(a + "," + b);
        }

        add1(10, 20);
        let add2 = function (a, b) {
            console.log(a + "," + b);
        };
        add2(10, 20);
        //()=>{}lambda表达式
        let add3 = a => a+=20;
        let number = add3(10);
        console.log(number);
    </script>
</head>
<body>

</body>
</html>